Head-Up Display Device and Display Control Method

1. A head-up display device, comprising: a reflection member disposed in front of a driver who drives a vehicle; a projector configured to project light toward the reflection member and display a virtual image in a region superimposed on a superimposing display target that is a detection target in front of the vehicle when viewed from the driver; and an imaging unit configured to take an image of a region in front of the vehicle to generate a front image that is an image of the region in front of the vehicle, a processor configured to calculate a parallax between a viewpoint position of the driver and a position of the imaging unit, wherein a region of the superimposing display target that is the detection target in front of the vehicle is divided into a plurality of divided regions, the projector adjusts a luminance distribution of the virtual image that is displayed in the region superimposed on the superimposing display target in accordance with a luminance distribution of a region of the superimposing display target that is the detection target in front of the vehicle in the front image, and adjusts luminance of a portion in the virtual image that corresponds to the divided region in accordance with a luminance value of the divided region, and a size of the divided region is changed in accordance with a size of the parallax.

2. The head-up display device according to claim 1 , wherein when a portion with low luminance is present in a region of the superimposing display target that is the detection target in front of the vehicle, the projector decreases luminance of a portion in the virtual image that corresponds to the portion with low luminance.

3. The head-up display device according to claim 2 , wherein the superimposing display target is the detection target in front of the vehicle that is detected by a detection unit.

4. The head-up display device according to claim 1 , wherein the superimposing display target is the detection target in front of the vehicle that is detected by a detection unit.

5. The head-up display device according to claim 4 , wherein the detection target is a mobile object in front of the vehicle, and the virtual image displayed by the projector is a frame surrounding the mobile object.

6. A display control method, comprising: an acquisition step of acquiring a front image that is an image of a region in front of a vehicle; and a projection step of projecting light toward a reflection member disposed in front of a driver who drives the vehicle, and displaying a virtual image in a region superimposed on a superimposing display target that is a detection target in front of the vehicle when viewed from the driver, wherein a region of the superimposing display target that is the detection target in front of the vehicle is divided into a plurality of divided regions, in the projecting step, a luminance distribution of the virtual image that is displayed in the region superimposed on the superimposing display target is adjusted in accordance with a luminance distribution of a region of the superimposing display target that is a detection target in front of the vehicle in the front image, and luminance of a portion in the virtual image that corresponds to a divided region is adjusted in accordance with a luminance value of the divided region, and a size of the divided region is changed in accordance with a size of a parallax between a viewpoint position of the driver and a position of an imaging unit configured to take the front image.

7. The display control method according to claim 6 , wherein in the projecting step, when a portion with low luminance is present in the front image, luminance of a portion in the virtual image that corresponds to the portion with low luminance is decreased.

8. The display control method according to claim 7 , wherein the superimposing display target is the detection target in front of the vehicle that is detected by a detection unit.

9. The display control method according to claim 6 , wherein the superimposing display target is the detection target in front of the vehicle that is detected by a detection unit.